Ductor roll accelerating mechanism

ABSTRACT

An improved printing press includes an ink fountain or supply roll which is driven at a relatively low peripheral speed and an ink train or receiving roll which is driven at a relatively high peripheral speed by the printing press drive. Ink is transferred between these two rolls by a ductor roll. To tend to minimize rotational shock loading on the printing press drive, the ductor roll is accelerated to the peripheral speed of the ink train roll under the influence of a motor which is independent of the printing press drive before the ductor roll engages the ink train roll.

United States Patent ['72] inventor Ernest iLTr-efl Groton, Conn. [21] Appl. No. 853,139 [22] Filed Aug. 26, 1969 [45] Patented July 6, 1971 [73] Assignee Harris lntertype Corporation Cleveland, Ohio [54] DUCTOR ROLL ACCELERATING MECHANlSM 11 Claims, 3 Drawing Figs.

[52] U.S.Cl 101/350 [51] 1nt.Cl B41f31/10 [50] Field otSearch 101/350, 351, 148

[ 56] References Cited UNITED STATES PATENTS 615,031 1898 Malmborg 101/350 X 668,035 1901 Clymeretal 101/350X 701,119 1902 Wood 101/350 752,285 i904 Davis 1,343,931 6/1920 Raabe 2,086,191 7/1937 Rutkoskie 2,120,978 6/1938 Huck re.20,458 7/1937 Schlesinger Primary Examiner-Robert E. Pulfrey Assistant Examiner-C. Coughenour Attarney-Yount and Tarolli 101/350 101/350X l0l/350X ABSTRACT: An improved printing press includes an ink fountain or supply roll which is driven at a relatively low peripheral speed and an ink train or receiving roll which is driven at a relatively high peripheral speed by the printing press drive. lnk is transferred between these two rolls by a ductor roll. To tend to minimize rotational shock loading on the printing press drive, the ductor roll is accelerated to the peripheral speed of the ink train roll under the influence of a motor which is independent of the printing press drive before the ductor roll engages the ink train roll.

DUCTOR ROLL ACCELERATING MECHANISM This invention relates generally to a printing press and more specifically to a mechanism for accelerating a ductor roll which transfers fluid from one roll to another roll in a printing press.

During normal operation of a printing press, the ductor roll in an inker assembly turns at a relatively low peripheral speed while the ductor roll is in contact with and receives ink from the fountain roll. The ductor roll then traverses the distance between the fountain roll and the first ink-receiving roll in the ink train. During this movement, the ductor roll either continues to rotate at the low peripheral speed of the fountain roll or comes to a standstill as a result of friction in the ductor roll bearings. When the ductor roll contacts the first ink-receiving roll in the ink train, it is necessary for the ink train roll to transfer a significant amount of rotational energy to the ductor roll in order to bring it up to the relatively high peripheral speed of the ink train roll. Since the train roll is driven by the press drive, this results in rotational shock loading on the press drive and has an adverse affect on instantaneous register and other printing quality factors.

Accordingly, it is an object of this invention to provide a new and improved printing press having a motor for accelerating an ink ductor roll independently of the printing press drive before the ductor roll contactsan ink-receiving roll in the ink train.

Another object of this invention is to provide a new and improved printing press having separately driven means for accelerating an ink ductor roll before it contacts an ink-receiving roll of an ink train wherein the means for accelerating the ductor roll is a separately driven roll which does not derive its power from the press drive.

It is another object of this invention to provide a new and improved printing press in accordance with the next preceding object and wherein the ductor roll remains in contact with the separately driven roll while ink is transferred to the ink-receiving roll in order to insure a smooth transfer of ink.

Another object of this invention is to provide a new andimproved printing press which includes a ductor roll which is movable between a first position engaging an ink supply roll and a second position engaging an ink-receiving roll to transport ink from the ink supply roll to the ink-receiving roll wherein a source of power independent of the press drive is provided for accelerating the ductor roll to the peripheral speed of the ink-receiving roll during movement of the ductor roll from the first position to the second position to thereby tend to minimize changes in the load on the press drive upon engagement of the ductor roll with the ink-receiving roll.

These and other objects and features of the invention will become more apparent upon a consideration of the following description taken in connection with the accompanying drawings wherein:

FIG. 1 is a highly schematized illustration of a printing press constructed in accordance with the present invention:

HO. 2 is a schematic illustration of a ductor-roll-accelerating mechanism forming a specific preferred embodiment of the present invention: and

FIG. 3 is a schematic elevational view, taken generally along the line 3-3 of FIG. 2, further illustrating the construction of the ductor-rolLaccelerating mechanism.

Although it is contemplated that a ductor-roll-accelerating mechanism constructed in accordance with the present invention can be utilized to accelerate a ductor roll associated with different parts of a printing press, a ductor-roll-accelerating mechanism is illustrated in FIG. 1 in association with an inker assembly 12 of a lithographic printing press 14. The lithographic printing press 14 includes a pair of blanket cylinders l8 and for printing on opposite sides of a web 22. The blanket cylinder 18 cooperates with a plate cylinder 26 to which ink is applied in a known manner by the inker assembly 12 and to which moisture is applied by a dampener assembly 28. Of course, an inker assembly and dampenef assembly cooperate with a plate cylinder (not shown) which engages the blanket cylinder 20.

The inker assembly 12 includes a plurality of rollers forming an ink train 32 which spreads a film ofink until it becomes sufficiently thin for application to a printing plate on the plate cylinder 26. In accordance with common practice, the rolls of the ink train 32 are driven by the press drive, indicated sche matically at 36 in FIG. 1. The press drive 36 also drives the blanket cylinders 18 and 20 and the associated plate cylinders through a suitable gear arrangement.

In addition to the ink train 32, the inker assembly 12 includes an ink fountain or supply 40 having a fountain or ink supply roll 42 which is driven at a relatively low peripheral speed by a motor 44. However, if desired the fountain roll 42 could be driven by the press drive 36. A ductor roll 48 transports ink from the slowly rotating fountain roll 42 to the first or ink-receiving roll 52 of the ink train 32. The ink train roll 52 is driven at a relatively high peripheral speed, compared to the fountain roll 42, by the press drive 36.

When the ductor roll 48 is in engagement with the fountain roll 42 (as shown in dashed lines in FIG. 2), the ductor roll is driven at a relatively low peripheral speed by the fountain roll. After a coating of ink has been applied to the ductor roll 48 by the fountain roll 42, the ductor roll is swung by a known drive arrangement, indicated schematically at 54 in FIG. 1, into engagement with the ink train roll 52 (as shown in solid lines in FIG. 2). The ductor roll 48 is maintained in engagement with the ink train roll 52 long enough to transfer a coating of ink to the roll 52. During this engagement of the ductor roll 48 with the ink train roll 52, the ductor roll is driven at the relatively high peripheral speed of the ink train roll. After a coating of ink has been transferred to the ink train roll 52, the ductor roll 48 is moved back into engagement with the fountain roll 42.

if the ductor roll 48 is brought into engagement with the ink train roll 52 while rotating at the relatively low peripheral speed of the fountain roll 42, the ductor roll will be accelerated to the peripheral speed of the ink train roll 52 by the ink train roll. This results in the application of a transient load on the press drive 36 and tends to cause instantaneous color misregister or "doubling due to rotational shock loading on the press drive 36.

ln accordance with the present invention, the ductor roll 48 is accelerated to the peripheral speed of the ink train roll 52 by a source of power which is independent of the press drive 36 before the ductor roll is moved into engagement with the ink train roll. This prevents shock loading of the press drive 36 upon engagement of the ductor roll 48 with the ink train roll 52 by eliminating the necessity for a transfer of rotational energy from the ink train roll to the ductor roll to accelerate the ductor roll. ln the illustrated embodiment of the invention, the ductor-roll-accelerating mechanism 10 includes an accelerator or drive roll 60 (FIG. 2) which is driven by a motor 62 through a chain drive 64. The motor 62 drives the roll 60 at the same peripheral speed as the ink train roll 52. Although the specific preferred ductor-roll-accelerating mechanism 10 includes the drive roll 60 which is driven by the motor 62 independently of the press drive 36, it is contemplated that other ductor-roll-accelerating mechanisms which include a source of power independent of the press drive could be utilized.

When the ductor roll 48 is in engagement with the fountain roll 42, that is in the position illustrated in dashed lines in FIG. 2, the ductor roll 48 is spaced from the drive roll 60. lmmediately after the ductor roll 48 is moved out of engagement with the fountain roll 42, the ductor roll 48 moves into en gagement with the drive roll 60. Since the drive roll 60 is driven at the same peripheral speed as the ink train roll 52, the drive roll 60 accelerates the ductor roll 48 to the peripheral speed of the ink train roll 52 before the ductor roll is brought into engagement with the ink train roll. Therefore, when the ductor roll engages the ink train roll 52, that is when the duetor roll is in a position illustrated in solid lines in FIG. 2, the shock load applied to the printing press drive 36 (FIG. 1) by the ink train roll 52 is minimized. To insure a a smooth transfer of ink from the ductor roll 48 to the ink train roll 52, the ductor roll 48 remains in contact with the drive roll 60 while ink is transferred from the ductor roll to the ink train roll. This contact enables the drive roll 60 to tend to smooth or work the ink on the ductor roll 48 in the same manner in which the ink is normally smoothed or worked by the distributor rolls of the ink train.

It should be noted that the ductor roll 48 is accelerated to the speed of the ink train roll 52 by the drive roll 60 under the influence of the motor 62 which is independent of the press drive 36. Therefore, the ductor roll 48 is accelerated from the relatively low peripheral speed of the fountain roll 42 to the relatively high peripheral speed of the ink train roll 52 without subjecting the press drive 36 to a changing load. Since this arrangement tends to minimize transient loadings on the press drive 36, the blanket cylinders 18 and 20 and other cylinders of the printing press 14 are driven at a relatively constant speed without variations induced as a result of acceleration of the ductor roll 48.

After the ductor roll 48 has been brought into initial engagement with the drive roll 60, the movement of the ductor roll toward the ink train roll 52 is continued. During this con-' tinued movement of the ductor roll 48 toward the ink train roll 52, the ductor roll tends to force the drive roll 60 upwardly or outwardly. Therefore, the drive roll 60 is mounted for movement relative to a frame 70 of the printing press 14 by a pair of mounting assemblies 74 and 76 (see HO. 3). The mounting assemblies 74 and 76 include support blocks 80 and 82 having suitable bearings 84 and 86 which support opposite ends of the drive roll 60 for rotation relative to the frame 70.

To provide for upward or outward movement of the drive roll 60 under the influence of the ductor roll 48, the support blocks 80 and 82 are threadedly connected to shafts 88 and 90 which are movable axially relative to connector blocks 94 and 96 against the influence of biasing springs 98 and 100. The biasing springs 98 and 100 are compressed between the support blocks 80 and 82 and the associated connector blocks 94 and 96 when the ductor roll 48 presses the drive roll 60 upwardly. The threaded shafts 88 and 90 have end portions 104 and 106 which enable the shafts to be rotated relative to the internally threaded support blocks 80 and 82 to adjust the position of the drive roll 60. In addition, the position of the connector blocks 94 and 96 can be adjusted relative to the frame 70 by means of screws 110 and 112.

In view of the foregoing description, it can be seen that the ductor roll 48 is accelerated to the peripheral speed of the ink train or receiving roll 52 independently of the press drive 36 before the ductor roll is brought into engagement with the ink train roll. Although the ductor roll 48 can be accelerated in many different ways, in the illustrated embodiment of the invention the ductor roll is accelerated by engagement with a drive roll 60. The drive roll 60 is driven by a motor 62 which is independent of the press drive. The transient load resulting from accelerating the ductor roll 48 is applied to the motor 62 so as to tend to minimize changes in the load applied to the press drive 36. The ductor roll 48 advantageously remains in engagement with the drive roll 60 while the ductor roll engages the ink train roll 52 to provide for a smooth transfer ofink to the ink train roll.

Although the ductor roll 48 has been illustrated herein as transferring ink from the fountain or supply roll 42 to the ink train or receiving roll 52, it is contemplated that the ductor roll could be located at other locations in the ink train 32. It is also contemplated that the ductor-roll-accelerating mechanism could be used to accelerate ductor rolls associated with assemblies or mechanisms other than the inker assembly 12. For example, the ductor-roll-accelerating mechanism 10 could be utilized in association with a ductor roll in a dampener assembly, similar to the dampener assembly 28.

Having described a preferred embodiment of the invention, I claim the following:

1. An assembly for use in a printing press having at least one printing cylinder, said assembly comprising an ink supply roll driven at a first peripheral speed, an ink-receiving roll driven at a second peripheral speed which is faster than said first peripheral speed, a ductor roll movable between a first position engaging said ink supply roll and a second position engaging said ink-receiving roll to transport ink from said ink supply toll to said ink-receiving roll, first power means for driving said ink-receiving roll and the printing cylinder, second power means independent of said first power means for accelerating said ductor roll to said second peripheral speed during movement of said ductor roll from said first position to said second position to thereby tend to minimize changes in the load on said first power means upon engagement of said ductor roll with said ink-receiving roll.

2. An assembly as set forth in claim 1 wherein said first power means including first motor means for driving the printing cylinder and said ink-receiving roll, said second power means including second motor means for driving said ductor roll independently of said first motor means.

3. An assembly as set forth in claim 1 wherein said second power means includes a drive roll which is driven at said second peripheral speed and is engageable by said ductor roll during movement of said ductor roll between said first and second positions to thereby enable said drive roll to accelerate said ductor roll to said second peripheral speed before said ductor roll reaches said first position.

4. An assembly as set forth in claim 3 wherein said ductor roll engages said drive roll when said ductor roll is in said second position.

5. An assembly as set forth in claim 1 wherein said second power means is ineffective to drive said ductor roll when said ductor roll is in said first position.

6. An assembly for use in a printing press, said assembly comprising a first roll mounted for rotation about a first axis, a second roll mounted for rotation about a second axis and spaced apart from said first roll, a ductor roll mounted for rotation about a third axis and movable between a first position in which said ductor roll engages said first roll and is spaced apart from said second roll and a second position in which said ductor roll engages said second roll and is spaced apart from said first roll to thereby provide for a transfer of fluid from said first roll to said second roll by said ductor roll, first means for driving said first roll at a first peripheral speed and for driving said second roll at a second peripheral speed which is faster than said first peripheral speed, second means for increasing the peripheral speed of said ductor roll to said second peripheral speed independently of said first means during movement of said ductor roll form said first position to i said second position to thereby tend to minimize changes in the load on said first means upon engagement of said ductor roll with said second roll.

7. An assembly as set forth in claim 6 wherein said first means includes a first motor for driving said second roll and said second means includes a second motor for driving said ductor roll during movement of said ductor roll from said first position to said second position.

8. An assembly as set forth in claim 7 wherein said second motor is operable to drive said ductor roll when said ductor roll is in said second position.

9. An assembly as set forth in claim 7 wherein said second means further includes a drive roll mounted for rotation about a fourth axis and engageable by said ductor roll during movement of said ductor roll from said first position to said second position and means for drivingly connecting said second motor to said drive roll to enable said second motor to effect rotation of said drive roll at a speed corresponding to said second peripheral speed, said drive roll being spaced apart from said first and second rolls.

10. An assembly as set forth in claim 9 further including resilient mounting means for enabling relative movement to occur between said third and fourth axes of rotation upon engagement of said ductor roll with said driye roll.

motor is mounted in a fixed relationship with said first and second axes of rotation. 

1. An assembly for use in a printing press having at least one printing cylinder, said assembly comprising an ink supply roll driven at a first peripheral speed, an ink-receiving roll driven at a second peripheral speed which is faster than said first peripheral speed, a ductor roll movable between a first position engaging said ink supply roll and a second position engaging said ink-receiving roll to transport ink from said ink supply toll to said ink-receiving roll, first power means for driving said inkreceiving roll and the printing cylinder, second power means independent of said first power means for accelerating said ductor roll to said second peripheral speed during movement of said ductor roll from said first position to said second position to thereby tend to minimize changes in the load on said first power means upon engagement of said ductor roll with said inkreceiving roll.
 2. An assembly as set forth in claim 1 wherein said first power means including first motor means for driving the printing cylinder and said ink-receiving roll, said second power means including second motor means for driving said ductor roll independently of said first motor means.
 3. An assembly as set forth in claim 1 wherein said second power means includes a drive roll which is driven at said second peripheral speed and is engageable by said ductor roll during movement of said ductor roll between said first and second positions to thereby enable said drive roll to accelerate said ductor roll to said second peripheral speed before said ductor roll reaches said first position.
 4. An assembly as set forth in claim 3 wherein said ductor roll engages said drive roll when said ductor roll is in said second position.
 5. An assembly as set forth in claim 1 wherein said second power means is ineffective to drive said ductor roll when said ductor roll is in said first position.
 6. An assembly for use in a printing press, said assembly comprising a first roll mounTed for rotation about a first axis, a second roll mounted for rotation about a second axis and spaced apart from said first roll, a ductor roll mounted for rotation about a third axis and movable between a first position in which said ductor roll engages said first roll and is spaced apart from said second roll and a second position in which said ductor roll engages said second roll and is spaced apart from said first roll to thereby provide for a transfer of fluid from said first roll to said second roll by said ductor roll, first means for driving said first roll at a first peripheral speed and for driving said second roll at a second peripheral speed which is faster than said first peripheral speed, second means for increasing the peripheral speed of said ductor roll to said second peripheral speed independently of said first means during movement of said ductor roll form said first position to said second position to thereby tend to minimize changes in the load on said first means upon engagement of said ductor roll with said second roll.
 7. An assembly as set forth in claim 6 wherein said first means includes a first motor for driving said second roll and said second means includes a second motor for driving said ductor roll during movement of said ductor roll from said first position to said second position.
 8. An assembly as set forth in claim 7 wherein said second motor is operable to drive said ductor roll when said ductor roll is in said second position.
 9. An assembly as set forth in claim 7 wherein said second means further includes a drive roll mounted for rotation about a fourth axis and engageable by said ductor roll during movement of said ductor roll from said first position to said second position and means for drivingly connecting said second motor to said drive roll to enable said second motor to effect rotation of said drive roll at a speed corresponding to said second peripheral speed, said drive roll being spaced apart from said first and second rolls.
 10. An assembly as set forth in claim 9 further including resilient mounting means for enabling relative movement to occur between said third and fourth axes of rotation upon engagement of said ductor roll with said drive roll.
 11. An assembly as set forth in claim 7 wherein said second motor is mounted in a fixed relationship with said first and second axes of rotation. 